The following documents by Joseph Little & his team are relevant to the use of Wufi:
Historic Scotland Technical Paper 15 - Assessing insulation retrofits with hygrothermal simulations – Heat and moisture transfer in insulated solid stone walls (.pdf)
Published in http://www.historic-scotland.gov.uk/technicalpapers
Breaking the Mould IV: Condensation risk analysis – the standards & the issues (.pdf)
Published in Construct Ireland (Issue 11, Vol. 4, 2010)
Breaking the Mould V: Comparative simulations of internal insulation systems (.pdf)
Published in Construct Ireland (Issue 12, Vol. 4, 2010)
The website of Fraunhofer IBP has an extensive database of freely downloadable publications about use of Wufi and research in hygrothermal calculation.